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into a larger-diameter chromatin fiber, which then folds into larger loops juste before cell didvidsion takes place, DNA replicates and the loops condense even more, forming a pair of chromatids pair of chromatids = chromosome
●●○○○3.6 Protein Synthesis proteome = all the organisms proteinsgene expression — process in which a geneʼs DNA is used as a template for synthesis of a specific protein transcription — the info encoded in a specific region of DNA is transcribed (copied) to produce a specific molecule of RNA translation — the RBNA attaches to a ribosome , where the info contained in RNA is translated into a corresponding sequence of AA to form a new protein molecule base triplet — a sequence of 3 nucleotides in DNA also called codon
○○●○○◆◆◆○◆○◆○◆◆○◆○○○◆◆○◆◆●○○A given codon specifies a particular AAgenetic code — the set of rules that relate the base triplet sequence of DNA to the corresponding codons of RNA and the AA they specify Transcription occurs in the nucleus 3 types of RNA are made from the genetic info represented by the sequence of base triplets in DNAMessenger RNA (mRNA) — directs synthesis of a proteinRibosomal RNA (rRNA) — joins with ribosomal proteins to make ribosomesTransfer RNA (tRNA) — binds to an AA and holds it in place on a ribosome until it is incorporated into a protein during translationRNA polymerase — catalyzes transcription of DNAmust be instructed where to start transcription process and where to end it promoter —a special nucleotide sequence, segment of DNA where transcription begins where RNA polymerase attaches to the DNADuring the process base pair in a complementary manner DNA - RNAATGC - UACGterminator — special nucleotide that specifies the end of the gene RNA polymerase reaches there and detaches from the transcribed RNA molecules and DNA strandintrons — regions within a gene that do not code for parts of proteinsexons — regions of DNA that do code for segments of a proteinimmediately after transcription, the transcript includes info from both introns and axons and is called pre-mRNAintrons are removed from pre-mRNA by small nuclear ribonucleoproteins (snRNPs) — enzymes that cut out the introns and splice together the axons resulting product is a functional mRGNA molecule that posses through a pore in the nuclear envelope to reach the cytoplasm, where translation takes place less genes, making a lot of proteins dude to alternative splicing of mRNA — a process in which the pre-mRNA transcribed from a gene is spliced in different ways to produce several different mRNAs diff mRNAs then translated into diff proteins Translationthe nucleotide sequence in an mRNA molecule specifies the AA sequence of a protein carried out by ribosomes
◆◆◆◆small subunit of a ribosomes has a binding site for mRNA, the larger subunit has three binding sites for tRNA molecules, a P site, A site and E site